The logo on your Irish SIM is only the start of the answer. Your USA cost depends on the exact plan, add-on, allowance and timing attached to your number.
Picture the moment after landing: aeroplane mode is off, your phone reconnects and you need maps, a lift or a message home. That is a poor time to discover that the roaming option you had in mind was for a different tariff. A five-minute check before departure can tell you whether you already have enough data, need an add-on or would be better served by a separate travel eSIM.
Published 11 September 2026 · Editorially updated 12 September 2026 · Source checks last completed 11 September 2026 · Editorial image is illustrative · Commercial disclosure: suitcase.ie sells travel eSIMs.
Check your existing allowance first
Start in your provider app or contract and look specifically for USA roaming. A general “roaming included” message may refer only to Europe. Note the exact plan name, whether it is bill pay or prepay, any included USA data and the date on which the allowance resets. If that allowance covers the trip, there may be no extra data cost at all.
Two Vodafone or Three customers can face different rules because of plan eligibility, existing roaming products, spending controls and the time at which a pass resets or expires.
How the current consumer options differ
Price is only one part of the comparison. The table also shows how much data the option provides, how long it lasts and whether the published terms are complete enough to estimate your trip.
| Operator and option | Eligibility | Allowance and validity | Price | Verification |
|---|---|---|---|---|
| VODAFONE Roam Extra weekly data bundle | bill pay / prepay | 5,120MB 8 day validity | €20.00 | Ready for a like-for-like estimate |
| VODAFONE Vodafone World USA daily data | bill pay / prepay | 1,024MB 1 day validity | €5.00 | Ready for a like-for-like estimate |
| THREE Roaming Day Pass 2GB | bill pay | 2,000MB 1 day validity | €5.99 | Ready for a like-for-like estimate |
| THREE 3 Days Roaming Pass | bill pay | 6,000MB 3 day validity | €14.99 | Ready for a like-for-like estimate |
| THREE 7 Days Roaming Pass | bill pay | 14,000MB 7 day validity | €34.99 | Ready for a like-for-like estimate |
| EIR USA 1GB data add-on | bill pay | 1,000MB Validity not established | €29.99 | Confirm the missing terms before costing |
Daily products and pooled bundles behave differently. A daily pass can reset at Irish midnight, while a pooled bundle can expire after a fixed number of days. A spending block can interrupt data; it is not a promise that all requested data is delivered for the capped amount.
What the fixed 5GB / seven-day benchmark can and cannot tell you
The benchmark uses exactly 5,000MB over seven consecutive days, with data used every day. It is useful for comparing different charging structures on one consistent basis. It is not your bill, an observed average traveller spend or a guarantee of saving.
Accepted scenarios are averaged within each provider first; provider means then receive equal weight. Missing or unverified scenarios are excluded rather than treated as zero. The aggregate is suppressed when fewer than two providers have accepted evidence.
What a data-only comparison excludes
Calls, voicemail, SMS, MMS, premium numbers and your normal Irish monthly subscription are outside these estimates. Leaving the Irish line active can still create chargeable activity even when mobile data uses another line.
suitcase.ie sells travel eSIMs. The comparison can recommend keeping an existing allowance, using a smaller plan or not buying a suitcase.ie plan when that follows from the entered evidence.
Download the comparison data
The CSV lists the public tariff details, source dates and whether a row can be used in a calculation. Rows with incomplete terms remain visible so you can see why they are not priced. It contains no supplier costs, margins or customer data.
Download USA roaming comparison (CSV)Decide after checking your own plan
If your current plan does not cover the trip, compare its verified incremental cost with the live allowance and validity of a suitable alternative.
See current USA eSIM plansEvidence
Sources
- Vodafone Ireland: Roaming rates and weekly data bundlesChecked 2026-09-11 · Eligibility and charging priority depend on the customer's plan. RED Roaming can take priority.
- Vodafone Ireland: Travelling abroad supportChecked 2026-09-11
- Three Ireland: Three Roaming Passes Billpay Add-onsChecked 2026-09-11 · Consumer bill-pay terms. Temporary 9GB and 21GB promotions expired on 26 August 2026 and are excluded.
- Three Ireland: Roaming guidanceChecked 2026-09-11
- eir: eir Mobile consumer bill-pay price list, part 12.2Checked 2026-09-11 · The published 1GB USA add-on does not establish validity, stacking or repeat purchases, so no 5GB eir scenario is accepted.
Tariffs, coverage and transport arrangements can change. Check the linked provider or operator source before relying on a time-sensitive detail. Material corrections are reflected on this page and in its evidence record.
Continue planning
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